Animals are the movers of the living world — everything from a 150-tonne whale to a frog smaller than a fingernail. Around 1.5 million species have been described, yet the best estimates put the true total near 8.7 million, meaning most animal life on Earth is still without a name.
Play the Animals quiz8.7M
Estimated species
1.5M
Described so far
96%
Are invertebrates
1M+
Threatened species
The animal kingdom, counted
Named species by group — the invertebrates dwarf everything with a backbone.
Insects
Beetles alone account for about 400,000 named species, one in four of all known animals.
~1.05M
Other arthropods
Spiders, scorpions, crabs, shrimps, centipedes and millipedes.
~150,000
Molluscs
Snails, slugs, clams, squid and octopuses.
~85,000
Vertebrates
Fish ~35,000, birds ~11,000, reptiles ~12,000, amphibians ~8,700, mammals ~6,500.
~70,000
Nematodes
Roundworms; four out of five land animals on the planet are thought to be nematodes.
~25,000
Record holders
The extremes of size, speed and endurance across the animal kingdom.
Blue whale
The largest animal ever known — bigger than any dinosaur, with a heart the size of a small car.
30 m · 150 t
≈ 98.4 ft, 165.3 tons
African elephant
The largest land animal; a herd can drink 200 litres each per day.
up to 6 t
≈ 6.61 tons
Peregrine falcon
The fastest animal alive, measured during its hunting stoop.
389 km/h
≈ 241.7 mph
Cheetah
The fastest land animal, reaching full speed in about three seconds.
100 km/h
≈ 62.1 mph
Arctic tern
Migrates pole to pole each year, seeing more daylight than any other creature.
~90,000 km/yr
≈ 55,923 mi
Immortal jellyfish
Turritopsis dohrnii can revert to its juvenile form and begin its life cycle again.
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Where the wild things live
Habitat loss is the single biggest pressure on animal populations worldwide.
Tropical forests
Hold roughly half of all land species on about 7% of the land surface.
Coral reefs
Less than 0.1% of the ocean floor, sheltering around a quarter of all marine species.
Soil
A quarter of all known species live in soil, including the decomposers that keep forests alive.
Extinction pressure
IPBES estimates about one million species face extinction, many within decades, unless habitats recover.
Did you know?
- Invertebrates make up roughly 96% of all described animal species — the vertebrates are a rounding error.
- A teaspoon of healthy soil can contain more living organisms than there are people on Earth.
- The blue whale's call reaches 188 decibels and travels hundreds of kilometres through the deep ocean.
- Some tardigrades survive vacuum, radiation and temperatures near absolute zero by drying into a glass-like state.